The invention relates to a braking and damping device, in particular for movable pieces of furniture, having a fluid-cylinder in which two pistons are arranged in a linearly displaceable manner, wherein a piston is displaceable over a piston rod.
With modern furniture, braking and damping devices are being used increasingly in order to prevent a door of a piece of furniture which is slammed shut too forcefully or a drawer which is pushed into a furniture frame with too much force from hitting the end wall of the furniture frame. The oldest damping devices were formed from simple rubber buffers. More recently, pneumatic and hydraulic braking- and damping devices have been used.
In the case of drawers, they are preferably combined with a drawing-in device. Also, doors or flaps are in many instances provided with hinges which have a closure mechanism, which is then responsible, together with the damping device, for an optimum course of movement.
In the case of fluid damping devices, i.e. pneumatic or hydraulic damping devices with a linearly movable piston, it has been seen that with high speeds or large volumes, the damping effect of the fluid is insufficient to brake the moving piece of furniture adequately.
U.S. Pat. No. 4,877,226 therefore proposed a fluid damping device with a linearly movable piston wherein the piston radially expanded during the damping operation and pressed against the cylinder wall, so that in addition to the damping effect caused by the fluid, frictional damping occurred between the cylinder and piston.